The invention deals with a method for manufacturing a bristle area of a toothbrush formed by several folded bristle bundles consisting of plastics bristles; the bristle bundles are to begin with individually folded from a bristle package with a predetermined length of the bristles by means of a flat tappet and an anchor and are pressed by said tappet and anchor consecutively into dead end holes of the bristle area of the toothbrush and are solidly anchored therein.
It has been demanded from toothbrushes for some time now for reasons of dental medicine, that, apart from an optimum cleaning of the teeth, said toothbrushes are also to provide a gentle treatment of the gums. Therefore the bristles consisting of plastics material are not permitted to have any sharp edges, fan-outs or the like, at their free user ends, since this would lead to injury of the gums. For this reason the typical feature of a toothbrush of high quality consists in that the user ends of the individual bristles are rounded. This prevents injury to the gums and the aimed-for massaging effects of the rounded bristle ends is fully effective on the gums.
The rounding of the utilization ends of the bristles is preferably performed by a type of grinding process, wherein it is always to be assured, that all bristles of a bundle or the entire bristle area are rounded off uniformly. In a toothbrush where the individual bristle bundles are folded and are respectively secured by means of an anchor in the bristle field of the toothbrush, the bristle bundles having a greater length are to begin with cut to the same size and only then are the free bristle ends rounded-off. In another type of manufacture of a bristle field, where the individual bristle bundles are severed from an endless bristle strand, the individual bristles of a bristle bundle are already rounded at the utilization ends prior to their insertion into the toothbrush.
From the aspect of dental medicine one aims these days for the individual bristle bundles and/or the individual bristles in the bristle bundle to have a different length. This is meant to increase the cleaning effect in particular in the critical spaces between the teeth and to improve the effect of the massage. Herein high-/low cuts, which can extend longitudinally or laterally, wave-shaped cuts, V-shaped cuts and saw-shaped cuts are known. This differing length of the bristles can be achieved without any difficulty by a process where the individual bristle bundles are cut out of an endless bristle strand, are rounded on the utilization side and then, possibly after fusing of the attachment ends together are inserted or poured into a toothbrush.
In a method for the manufacture of a toothbrush, where the bristle bundles are to begin with separated individually out of a bristle package with predetermined length of the bristles, then are folded with the help of an anchor, are thereupon pressed and anchored consecutively by means of the anchor into the dead end holes of the bristle area of a toothbrush, this results in an impairment of the rounded off-shape. As is known in this method, the utilization side bristle ends of the bristles are rounded-off in one single work step after being cut-off. If this cut now does not run in one single plane, only the longer bristles of a bristle bundle or of the bristle area are rounded-off optimally. The bristle ends located lower are either inadequately or not at all swept by the processing tool, so that the lower lying bristle ends can still have sharp edges, fan-outs or the like. This means that with this fabrication process using the profiled cut when cutting the bristles or bristle bundles of a bristle field to size, the aimed-for quality of a high quality toothbrush cannot be achieved meaning the individual bristle ends are not optimally rounded-off. Herein it must also be taken into account, that dust accumulates in the course of the rounding-off process of the bristle ends of a bristle field of a toothbrush, which dust can attach itself in the bristle area and thus can no longer be completely removed, even with great effort.
Therefore the invention is based upon the task of providing a method for fabrication of a bristle area of a tooth brush, formed of a plurality of folded bristle bundles made from plastics bristles, where, even with conventional manufacture of the bristle area, meaning individualization or isolation, folding and attachment of the bristle bundle by means of an anchor, in a profiling of the bristle area with different bristle lengths, an optimum rounding-off of the bristle ends is feasible. In addition to this it is to be prevented that the dust accumulating when rounding-off the bristles can reach the toothbrush.